A second-generation series of biscyclometalated 2-(5-aryl-thienyl)-benzimidazole and -benzothiazole Ir(III) dppz complexes [Ir(C^N)2(dppz)]+, Ir1-Ir4, were rationally designed and synthesized, where the aryl group attached to the thienyl ring was p-CF3C6H4 or p-Me2NC6H4. These new Ir(III) complexes were assessed as photosensitizers to explore the structure-activity correlations for their potential use in biocompatible anticancer photodynamic therapy. When irradiated with blue light, the complexes exhibited high selective potency across several cancer cell lines predisposed to photodynamic therapy; the benzothiazole derivatives (Ir1 and Ir2) were the best performers, Ir2 being also activatable with green or red light. Notably, when irradiated, the complexes induced leakage of lysosomal content into the cytoplasm of HeLa cancer cells and induced oncosis-like cell death. The capability of the new Ir complexes to photoinduce cell death in 3D HeLa spheroids has also been demonstrated. The investigated Ir complexes can also catalytically photo-oxidate NADH and photogenerate 1O2 and/or •OH in cell-free media.

ACTI Universidad de Murcia Murcia E 30100 Spain

Czech Academy of Sciences Institute of Biophysics Kralovopolska 135 Brno CZ 61200 Czech Republic

Departamento de Química Inorgánica Universidad de Murcia and Biomedical Research Institute of Murcia Murcia E 30100 Spain

See more in PubMed

Sung H.; Ferlay J.; Siegel R. L.; Laversanne M.; Soerjomataram I.; Jemal A.; Bray F. Global cancer statistics 2020: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA: Cancer J. Clin. 2021, 71, 209–249. 10.3322/caac.21660. PubMed DOI

Oun R.; Moussa Y. E.; Wheate N. J. The side effects of platinum-based chemotherapy drugs: a review for chemists. Dalton Trans. 2018, 47, 6645–6653. 10.1039/C8DT00838H. PubMed DOI

Thota S.; Rodrigues D. A.; Crans D. C.; Barreiro E. J. Ru(II) compounds: next-generation anticancer metallotherapeutics?. J. Med. Chem. 2018, 61, 5805–5821. 10.1021/acs.jmedchem.7b01689. PubMed DOI

Baier D.; Mendrina T.; Schoenhacker-Alte B.; Pirker C.; Mohr T.; Rusz M.; Regner B.; Schaier M.; Sgarioto N.; Raynal N. J.-M.; Nowikovsky K.; Schmidt W. M.; Heffeter P.; Meier-Menches S. M.; Koellensperger G.; Keppler B. K.; Berger W. The lipid metabolism as target and modulator of BOLD-100 anticancer activity: Crosstalk with histone acetylation. Adv. Sci. 2023, 10 (32), 230193910.1002/advs.202301939. PubMed DOI PMC

Zhou X. Q.; Wang P.; Ramu V.; Zhang L.; Jiang S.; Li X.; Abyar S.; Papadopoulou P.; Shao Y.; Bretin L.; Siegler M. A.; Buda F.; Kros A.; Fan J.; Peng X.; Sun W.; Bonnet S. In vivo metallophilic self-assembly of a light-activated anticancer drug. Nat. Chem. 2023, 15, 980–987. 10.1038/s41557-023-01199-w. PubMed DOI PMC

Deng Z.; Li H.; Chen S.; Wang N.; Liu G.; Liu D.; Ou W.; Xu F.; Wang X.; Lei D.; Lo P.-C.; Li Y. Y.; Lu J.; Yang M.; He M.-L.; Zhu G. Near-infrared-activated anticancer platinum(IV) complexes directly photooxidize biomolecules in an oxygen-independent manner. Nat. Chem. 2023, 15, 930–939. 10.1038/s41557-023-01242-w. PubMed DOI

Zhou H.; Tang D.; Yu Y.; Zhang L.; Wang B.; Karges J.; Xiao H. Theranostic imaging and multimodal photodynamic therapy and immunotherapy using the mTOR signaling pathway. Nat. Commun. 2023, 14, 5350.10.1038/s41467-023-40826-5. PubMed DOI PMC

Kuang S.; Wei F.; Karges J.; Ke L.; Xiong K.; Liao X.; Gasser G.; Ji L.; Chao H. Photodecaging of a mitochondria-localized iridium(III) endoperoxide complex for two-photon photoactivated therapy under hypoxia. J. Am. Chem. Soc. 2022, 144, 4091–4101. 10.1021/jacs.1c13137. PubMed DOI

Lee L. C.-C.; Lo K. K.-W. Luminescent and photofunctional transition metal complexes: From molecular design to diagnostic and therapeutic applications. J. Am. Chem. Soc. 2022, 144, 14420–14440. 10.1021/jacs.2c03437. PubMed DOI

Wei F.; Karges J.; Shen J.; Xie L.; Xiong K.; Zhang X.; Ji L.; Chao H. A mitochondria-localized oxygen self-sufficient two-photon nano-photosensitizer for ferroptosis-boosted photodynamic therapy under hypoxia. Nano Today 2022, 44, 10150910.1016/j.nantod.2022.101509. DOI

Wu Y.; Li S.; Chen Y.; He W.; Guo Z. Recent advances in noble metal complex based photodynamic therapy. Chem. Sci. 2022, 13, 5085–5106. 10.1039/D1SC05478C. PubMed DOI PMC

Su X.; Wang W.-J.; Cao Q.; Zhang H.; Liu B.; Ling Y.; Zhou X.; Mao Z.-W. A carbonic anhydrase IX (CAIX)-anchored rhenium(I) photosensitizer evokes pyroptosis for enhanced anti-tumor immunity. Angew. Chem., Int. Ed. 2022, 61, e20211580010.1002/anie.202115800. PubMed DOI

Imberti C.; Zhang P.; Huang H.; Sadler P. J. New designs for phototherapeutic transition metal complexes. Angew. Chem., Int. Ed. 2020, 59, 61–73. 10.1002/anie.201905171. PubMed DOI PMC

Echevarría I.; Zafon E.; Barrabés S.; Martínez M. Á.; Ramos-Gómez S.; Ortega N.; Manzano B. R.; Jalón F. A.; Quesada R.; Espino G.; Massaguer A. Rational design of mitochondria targeted thiabendazole-based Ir(III) biscyclometalated complexes for a multimodal photodynamic therapy of cancer. J. Inorg. Biochem. 2022, 231, 11179010.1016/j.jinorgbio.2022.111790. PubMed DOI

Mari C.; Pierroz V.; Ferrari S.; Gasser G. Combination of Ru(II) complexes and light: new frontiers in cancer therapy. Chem. Sci. 2015, 6, 2660–2686. 10.1039/C4SC03759F. PubMed DOI PMC

Roque J. A. III; Cole H. D.; Barrett P. C.; Lifshits L. M.; Hodges R. O.; Kim S.; Deep G.; Francés-Monerris A.; Alberto M. E.; Cameron C. G.; McFarland S. A. Intraligand excited states turn a ruthenium oligothiophene complex into a light-triggered ubertoxin with anticancer efects in extreme hypoxia. J. Am. Chem. Soc. 2022, 144, 8317–8336. 10.1021/jacs.2c02475. PubMed DOI PMC

Zhang Y.; Doan B.-T.; Gasser G. Metal-based photosensitizers as inducers of regulated cell death mechanisms. Chem. Rev. 2023, 123, 10135–10155. 10.1021/acs.chemrev.3c00161. PubMed DOI

Ortega-Forte E.; Rovira A.; López-Corrales M.; Hernández-García A.; Ballester F. J.; Izquierdo-García E.; Jordà-Redondo M.; Bosch M.; Nonell S.; Santana M. D.; Ruiz J.; Marchán V.; Gasser G. A near-infrared light-activatable Ru(ii)-coumarin photosensitizer active under hypoxic conditions. Chem. Sci. 2023, 14, 7170–7184. 10.1039/D3SC01844J. PubMed DOI PMC

Karges J.; Heinemann F.; Jakubaszek M.; Maschietto F.; Subecz C.; Dotou M.; Vinck R.; Blacque O.; Tharaud M.; Goud B.; Viñuelas Zahínos E.; Spingler B.; Ciofini I.; Gasser G. Rationally designed long-wavelength absorbing Ru(II) polypyridyl complexes as photosensitizers for photodynamic therapy. J. Am. Chem. Soc. 2020, 142, 6578–6587. 10.1021/jacs.9b13620. PubMed DOI

Monro S.; Colón K. L.; Yin H.; Roque J.; Konda P.; Gujar S.; Thummel R. P.; Lilge L.; Cameron C. G.; McFarland S. A. Transition metal complexes and photodynamic therapy from a tumor-centered approach: Challenges, opportunities, and highlights from the development of TLD1433. Chem. Rev. 2019, 119, 797–828. 10.1021/acs.chemrev.8b00211. PubMed DOI PMC

Shen J.; Rees T. W.; Ji L.; Chao H. Recent advances in ruthenium(II) and iridium(III) complexes containing nanosystems for cancer treatment and bioimaging. Coord. Chem. Rev. 2021, 443, 21401610.1016/j.ccr.2021.214016. DOI

Rovira A.; Ortega-Forte E.; Hally C.; Jordà-Redondo M.; Abad-Montero D.; Vigueras G.; Martínez J. I.; Bosch M.; Nonell S.; Ruiz J.; Marchán V. Exploring sructure–activity relationships in photodynamic therapy anticancer agents based on Ir(III)-COUPY conjugates. J. Med. Chem. 2023, 66, 7849–7867. 10.1021/acs.jmedchem.3c00189. PubMed DOI PMC

Tang S.-J.; Li Q.-F.; Wang M.-F.; Yang R.; Zeng L.-Z.; Li X.-L.; Wang R.-D.; Zhang H.; Ren X.; Zhang D.; Gao F. Bleeding the excited state energy to the utmost: Single-molecule iridium complexes for in vivo dual photodynamic and photothermal therapy by an infrared low-power laser. Adv. Healthcare Mater. 2023, 12 (28), 230122710.1002/adhm.202301227. PubMed DOI

Vigueras G.; Markova L.; Novohradsky V.; Marco A.; Cutillas N.; Kostrhunova H.; Kasparkova J.; Ruiz J.; Brabec V. A photoactivated Ir(III) complex targets cancer stem cells and induces secretion of damage-associated molecular patterns in melamoma cells characteristic of immunogenic cell death. Inorg. Chem. Front. 2021, 8, 4696–4711. 10.1039/D1QI00856K. DOI

Bevernaegie R.; Doix B.; Bastien E.; Diman A.; Decottignies A.; Feron O.; Elias B. Exploring the photo-toxicity of hypoxic active iridium(III)-based sensitizers in 3D tumor spheroids. J. Am. Chem. Soc. 2019, 141, 18486–18491. 10.1021/jacs.9b07723. PubMed DOI

Huang C.; Liang C.; Sadhukhan T.; Banerjee S.; Fan Z.; Li T.; Zhu Z.; Zhang P.; Raghavachari K.; Huang H. In-vitro and in-vivo photocatalytic cancer therapy with biocompatible iridium(III) photocatalysts. Angew. Chem., Int. Ed. 2021, 60, 9474–9479. 10.1002/anie.202015671. PubMed DOI

He L.; Li Y.; Tan C.-P.; Ye R.-R.; Chen M.-H.; Cao J.-J.; Ji L.-N.; Mao Z.-W. Cyclometalated iridium(III) complexes as lysosome-targeted photodynamic anticancer and real-time tracking agents. Chem. Sci. 2015, 6, 5409–5418. 10.1039/C5SC01955A. PubMed DOI PMC

Huang H.; Banerjee S.; Qiu K.; Zhang P.; Blacque O.; Malcomson T.; Paterson M. J.; Clarkson G. J.; Staniforth M.; Stavros V. G.; Gasser G.; Chao H.; Sadler P. J. Targeted photoredox catalysis in cancer cells. Nat. Chem. 2019, 11, 1041–1048. 10.1038/s41557-019-0328-4. PubMed DOI

Li M.; Xu Y.; Pu Z.; Xiong T.; Huang H.; Long S.; Son S.; Yu L.; Singh N.; Tong Y.; Sessler J. L.; Peng X.; Kim J. S. Photoredox catalysis may be a general mechanism in photodynamic therapy. Proc. Natl. Acad. Sci. U. S. A. 2022, 119, e221050411910.1073/pnas.2210504119. PubMed DOI PMC

Peng K.; Zheng Y.; Xia W.; Mao Z.-W. Organometallic anti-tumor agents: targeting from biomolecules to dynamic bioprocesses. Chem. Soc. Rev. 2023, 52, 2790–2832. 10.1039/D2CS00757F. PubMed DOI

Ortega-Forte E.; Hernández-García S.; Vigueras G.; Henarejos-Escudero P.; Cutillas N.; Ruiz J.; Gandía-Herrero F. Potent anticancer activity of a novel iridium metallodrug via oncosis. Cell. Mol. Life Sci. 2022, 79, 510.10.1007/s00018-022-04526-5. PubMed DOI PMC

Guan R.; Chen Y.; Zeng L.; Rees T. W.; Jin C.; Huang J.; Chen Z.-S.; Ji L.; Chao H. Oncosis-inducing cyclometalated iridium(III) complexes. Chem. Sci. 2018, 9, 5183–5190. 10.1039/C8SC01142G. PubMed DOI PMC

Novohradsky V.; Vigueras G.; Pracharova J.; Cutillas N.; Janiak C.; Kostrhunova H.; Brabec V.; Ruiz J.; Kasparkova J. Molecular superoxide radical photogeneration in cancer cells by dipyridophenazine iridium(III) complexes. Inorg. Chem. Front. 2019, 6, 2500–2513. 10.1039/C9QI00811J. DOI

Markova L.; Novohradsky V.; Kasparkova J.; Ruiz J.; Brabec V. Dipyridophenazine iridium(III) complex as a phototoxic cancer stem cell selective, mitochondria targeting agent. Chem. Biol. Interact. 2022, 360, 10995510.1016/j.cbi.2022.109955. PubMed DOI

Suárez-Moreno G. V.; Hernández-Romero D.; García-Barradas Ó.; Vázquez-Vera Ó.; Rosete-Luna S.; Cruz-Cruz C. A.; López-Monteon A.; Carrillo-Ahumada J.; Morales-Morales D.; Colorado-Peralta R. Second and third-row transition metal compounds containing benzimidazole ligands: An overview of their anticancer and antitumour activity. Coord. Chem. Rev. 2022, 472, 21479010.1016/j.ccr.2022.214790. DOI

Zajac M.; Hrobárik P.; Magdolen P.; Foltínová P.; Zahradník P. Donor−π-acceptor benzothiazole-derived dyes with an extended heteroaryl-containing conjugated system: synthesis, DFT study and antimicrobial activity. Tetrahedron 2008, 64, 10605–10618. 10.1016/j.tet.2008.08.064. DOI

Cao J. J.; Tan C. P.; Chen M. H.; Wu N.; Yao D. Y.; Liu X. G.; Ji L. N.; Mao Z. W. Targeting cancer cell metabolism with mitochondria-immobilized phosphorescent cyclometalated iridium(III) complexes. Chem. Sci. 2017, 8, 631–640. 10.1039/C6SC02901A. PubMed DOI PMC

Wang C.-t.; Chen J.; Xu J.; Wei F.; Yam C. Y.; Wong K. M.-C.; Sit P. H. L.; Teoh W. Y. Selective visible light reduction of carbon dioxide over iridium(III)-terpyridine photocatalysts. Materials Today Chem. 2021, 22, 10056310.1016/j.mtchem.2021.100563. DOI

Redrado M.; Miñana M.; Coogan M. P.; Gimeno M. C.; Fernández-Moreira V. Tunable emissive Ir(III) benzimidazole-quinoline hybrids as promising theranostic lead compounds. ChemMedChem 2022, 17, e20220024410.1002/cmdc.202200244. PubMed DOI PMC

Millán G.; Nieddu M.; López I. P.; Ezquerro C.; Berenguer J. R.; Larráyoz I. M.; Pichel J. G.; Lalinde E. A new family of luminescent iridium complexes: synthesis, optical, and cytotoxic studies. Dalton Trans. 2023, 52, 6360–6374. 10.1039/D3DT00028A. PubMed DOI

DiLuzio S.; Mdluli V.; Connell T. U.; Lewis J.; VanBenschoten V.; Bernhard S. High-throughput screening and automated data-driven analysis of the triplet photophysical properties of structurally diverse, heteroleptic iridium(III) complexes. J. Am. Chem. Soc. 2021, 143, 1179–1194. 10.1021/jacs.0c12290. PubMed DOI

Zhuang J.; Wang B.; Chen H.; Zhang K.; Li N.; Zhao N.; Tang B. Z. Efficient NIR-II type-I AIE photosensitizer for mitochondria-targeted photodynamic therapy through synergistic apoptosis–ferroptosis. ACS Nano 2023, 17, 9110–9125. 10.1021/acsnano.2c12319. PubMed DOI

Price M.; Reiners J. J.; Santiago A. M.; Kessel D. Monitoring singlet oxygen and hydroxyl radical formation with fluorescent probes during photodynamic therapy. Photochem. Photobiol. 2009, 85, 1177–1181. 10.1111/j.1751-1097.2009.00555.x. PubMed DOI PMC

Zhuang Z.; Dai J.; Yu M.; Li J.; Shen P.; Hu R.; Lou X.; Zhao Z.; Tang B. Z. Type I photosensitizers based on phosphindole oxide for photodynamic therapy: apoptosis and autophagy induced by endoplasmic reticulum stress. Chem. Sci. 2020, 11, 3405–3417. 10.1039/D0SC00785D. PubMed DOI PMC

Li Y.; Liu B.; Lu X.-R.; Li M.-F.; Ji L.-N.; Mao Z.-W. Cyclometalated iridium(III) N-heterocyclic carbene complexes as potential mitochondrial anticancer and photodynamic agents. Dalton Trans. 2017, 46, 11363–11371. 10.1039/C7DT01903C. PubMed DOI

Li Y.; Tan C.-P.; Zhang W.; He L.; Ji L.-N.; Mao Z.-W. Phosphorescent iridium(III)-bis-N-heterocyclic carbene complexes as mitochondria-targeted theranostic and photodynamic anticancer agents. Biomaterials 2015, 39, 95–104. 10.1016/j.biomaterials.2014.10.070. PubMed DOI

He L.; Zhang M.-F.; Pan Z.-Y.; Wang K.-N.; Zhao Z.-J.; Li Y.; Mao Z.-W. A mitochondria-targeted iridium(III)-based photoacid generator induces dual-mode photodynamic damage within cancer cells. Chem. Commun. 2019, 55, 10472–10475. 10.1039/C9CC04871E. PubMed DOI

van Engeland M.; Nieland L. J.; Ramaekers F. C.; Schutte B.; Reutelingsperger C. P. Annexin V-affinity assay: a review on an apoptosis detection system based on phosphatidylserine exposure. Cytometry 1998, 31, 1–9. 10.1002/(SICI)1097-0320(19980101)31:1<1::AID-CYTO1>3.0.CO;2-R. PubMed DOI

Lecoeur H.; Prévost M. C.; Gougeon M. L. Oncosis is associated with exposure of phosphatidylserine residues on the outside layer of the plasma membrane: a reconsideration of the specificity of the annexin V/propidium iodide assay. Cytometry 2001, 44, 65–72. 10.1002/1097-0320(20010501)44:1<65::AID-CYTO1083>3.0.CO;2-Q. PubMed DOI

Fink S. L.; Cookson B. T. Apoptosis, pyroptosis, and necrosis: mechanistic description of dead and dying eukaryotic cells. Infection and immunity 2005, 73, 1907–1916. 10.1128/IAI.73.4.1907-1916.2005. PubMed DOI PMC

Trump B. F.; Berezesky I. K.; Chang S. H.; Phelps P. C. The pathways of cell death: oncosis, apoptosis, and necrosis. Toxicol. Pathol. 1997, 25, 82–88. 10.1177/019262339702500116. PubMed DOI

Weerasinghe P.; Buja L. M. Oncosis: An important non-apoptotic mode of cell death. Exp. Mol. Pathol. 2012, 93, 302–308. 10.1016/j.yexmp.2012.09.018. PubMed DOI

Majno G.; Joris I. Apoptosis, oncosis, and necrosis: An overview of cell death. Am. J. Pathol. 1995, 146, 3–15. PubMed PMC

Vossenkamper A.; Warnes G. Flow cytometry reveals the nature of oncotic cells. Int. J. Mol. Sci. 2019, 20, 4379.10.3390/ijms20184379. PubMed DOI PMC

Liu L. F.; Qian Z. H.; Qin Q.; Shi M.; Zhang H.; Tao X. M.; Zhu W. P. Effect of melatonin on oncosis of myocardial cells in the myocardial ischemia/reperfusion injury rat and the role of the mitochondrial permeability transition pore. Genet. Mol. Res. 2015, 14, 7481–7489. 10.4238/2015.July.3.24. PubMed DOI

Wang F.; Gómez-Sintes R.; Boya P. Lysosomal membrane permeabilization and cell death. Traffic (Copenhagen, Denmark) 2018, 19, 918–931. 10.1111/tra.12613. PubMed DOI

Jing Y.; Kobayashi M.; Vu H. T.; Kasahara A.; Chen X.; Pham L. T.; Kurayoshi K.; Tadokoro Y.; Ueno M.; Todo T.; Nakada M.; Hirao A. Therapeutic advantage of targeting lysosomal membrane integrity supported by lysophagy in malignant glioma. Cancer Sci. 2022, 113, 2716–2726. 10.1111/cas.15451. PubMed DOI PMC

Barral D. C.; Staiano L.; Guimas Almeida C.; Cutler D. F.; Eden E. R.; Futter C. E.; Galione A.; Marques A. R. A.; Medina D. L.; Napolitano G.; Settembre C.; Vieira O. V.; Aerts J. M. F. G.; Atakpa-Adaji P.; Bruno G.; Capuozzo A.; De Leonibus E.; Di Malta C.; Escrevente C.; Esposito A.; Grumati P.; Hall M. J.; Teodoro R. O.; Lopes S. S.; Luzio J. P.; Monfregola J.; Montefusco S.; Platt F. M.; Polishchuck R.; De Risi M.; Sambri I.; Soldati C.; Seabra M. C. Current methods to analyze lysosome morphology, positioning, motility and function. Traffic 2022, 23, 238–269. 10.1111/tra.12839. PubMed DOI PMC

Santos S. A. C. S.; Persechini P. M.; Henriques-Santos B. M.; Bello-Santos V. G.; Castro N. G.; Costa de Sousa J.; Genta F. A.; Santiago M. F.; Coutinho-Silva R.; Savio L. E. B.; Kurtenbach E. P2 × 7 receptor triggers lysosomal leakage through calcium mobilization in a mechanism dependent on pannexin-1 hemichannels. Front. Immunol. 2022, 13, 75210510.3389/fimmu.2022.752105. PubMed DOI PMC

Cao M.; Luo X.; Wu K.; He X. Targeting lysosomes in human disease: from basic research to clinical applications. Signal Transduction Targeted Ther. 2021, 6, 379.10.1038/s41392-021-00778-y. PubMed DOI PMC

Piao S.; Amaravadi R. K. Targeting the lysosome in cancer. Ann. N.Y. Acad. Sci. 2016, 1371, 45–54. 10.1111/nyas.12953. PubMed DOI PMC

Zhu S.-Y.; Yao R.-Q.; Li Y.-X.; Zhao P.-Y.; Ren C.; Du X.-H.; Yao Y.-M. Lysosomal quality control of cell fate: a novel therapeutic target for human diseases. Cell Death Dis. 2020, 11, 817.10.1038/s41419-020-03032-5. PubMed DOI PMC

Zanoni M.; Piccinini F.; Arienti C.; Zamagni A.; Santi S.; Polico R.; Bevilacqua A.; Tesei A. 3D tumor spheroid models for in vitro therapeutic screening: a systematic approach to enhance the biological relevance of data obtained. Sci. Rep. 2016, 6, 19103.10.1038/srep19103. PubMed DOI PMC

Riedl A.; Schlederer M.; Pudelko K.; Stadler M.; Walter S.; Unterleuthner D.; Unger C.; Kramer N.; Hengstschläger M.; Kenner L.; Pfeiffer D.; Krupitza G.; Dolznig H. Comparison of cancer cells in 2D vs 3D culture reveals differences in AKT–mTOR–S6K signaling and drug responses. J. Cell Sci. 2017, 130, 203–218. 10.1242/jcs.188102. PubMed DOI

Wadman M. FDA no longer needs to require animal tests before human drug trials. Science 2023, 379, 127–128. 10.1126/science.adg6276. PubMed DOI

Wang H.; Xu T.; Yin D. Emerging trends in the methodology of environmental toxicology: 3D cell culture and its applications. Sci. Total Environ. 2023, 857, 15950110.1016/j.scitotenv.2022.159501. PubMed DOI

Kessel S.; Cribbes S.; Déry O.; Kuksin D.; Sincoff E.; Qiu J.; Chan L. L. High-throughput 3D tumor spheroid screening method for cancer drug discovery using celigo image iytometry. SLAS Technol. 2017, 22, 454–465. 10.1177/2211068216652846. PubMed DOI

Sirenko O.; Mitlo T.; Hesley J.; Luke S.; Owens W.; Cromwell E. F. High-content assays for characterizing the viability and morphology of 3D cancer spheroid cultures. Assay Drug Dev. Technol. 2015, 13, 402–414. 10.1089/adt.2015.655. PubMed DOI PMC

Costa S. P. G.; Ferreira J. A.; Kirsch G.; Oliveira-Campos A. M. F. New fluorescent 1,3-benzothiazoles by the reaction of heterocyclic aldehydes with ortho-aminobenzenethiol. J. Chem. Res. (S) 1997, 314–315. 10.1039/a702605f. DOI

Betti M.; Genesio E.; Marconi G.; Sanna Coccone S.; Wiedenau P. A scalable route to the SMO receptor antagonist SEN826: Benzimidazole synthesis via enhanced in situ formation of the bisulfite–aldehyde complex. Org. Process Res. Dev. 2014, 18, 699–708. 10.1021/op4002092. DOI

Skolia E.; Apostolopoulou M. K.; Nikitas N. F.; Kokotos C. G. Photochemical synthesis of benzimidazoles from damines and aldehydes. Eur. J. Org. Chem. 2021, 2021, 422–428. 10.1002/ejoc.202001357. DOI

Bruker . Bruker AXS Inc.: Madison, Wisconsin, USA, 2001.

Sheldrick G. M. Crystal structure refinement with SHELXL. Acta Crystallogr., Sect. C: Struct. Chem. 2015, 71, 3–8. 10.1107/S2053229614024218. PubMed DOI PMC

Spek A. L. PLATON SQUEEZE: a tool for the calculation of the disordered solvent contribution to the calculated structure factors. Acta Crystallogr. C Struct. Chem. 2015, 71, 9–18. 10.1107/S2053229614024929. PubMed DOI

Novohradsky V.; Markova L.; Kostrhunova H.; Kasparkova J.; Ruiz J.; Marchán V.; Brabec V. A cyclometalated IrIII complex conjugated to a coumarin derivative is a potent photodynamic agent against prostate differentiated and tumorigenic cancer stem cells. Chem. - Eur. J. 2021, 27, 8547–8556. 10.1002/chem.202100568. PubMed DOI

Pracharova J.; Vigueras G.; Novohradsky V.; Cutillas N.; Janiak C.; Kostrhunova H.; Kasparkova J.; Ruiz J.; Brabec V. Exploring the effect of polypyridyl ligands on the anticancer activity of phosphorescent iridium(III) complexes: From proteosynthesis inhibitors to photodynamic therapy agents. Chem. - Eur. J. 2018, 24, 4607–4619. 10.1002/chem.201705362. PubMed DOI